The present invention relates to an image storage system for storing image data such as a system using a network digital recorder (NDR) which is a device for acquiring, storing, and distributing image data via a network.
For example, a study is made on an image storage system for capturing an image of a predetermined region by a camera for monitoring, storing data on the captured image in an image storage device such as an NDR, and displaying the stored image data on a screen provided on a client such as a computer.
FIG. 25 shows a configuration example of an image storage system. It should be noted that like components substantially identical to those shown in FIG. 1 relating to the present invention which will be described later are denoted by like symbols (like symbols excluding A and B). However, this does not have an intention to limit the present invention.
A network 2 is a computer network for connecting a plurality of computers for communicating a control signal and a signal such as data.
A plurality (m pieces) of IP cameras (Internet Protocol Cameras) 3 (3-1 to 3-m) are provided for outputting captured image data to the network 2.
A plurality (n pieces) of client PC (Personal Computers) 4 (4-1 to 4-n) are provided as ordinary personal computers having a Web browser by network connection.
A network digital recorder (NDR) 1 is connected via the network 2 to the IP cameras (3-1 to 3-m) and a plurality of client PC 4 (4-1 to 4-n) for performing view of the image data and setting of the NDR 1.
The NDR 1 includes a computer board 12 and a recording device 11 as components.
On the computer board 12, there are arranged a network interface (network I/F) 14, a recording device interface (recording device I/F) 15, a memory 16, and a CPU (Central Processing Unit) 17 which are connected via a control bus 13.
In the recording device 11, there are provided recording regions 31 (31-1 to 31-m) for the respective cameras and a setting information file 19. The number of the camera recording regions 31 (31-1 to 31-m) is identical to the number of the IP cameras 3 (3-1 to 3-m) for recording. The regions 31 are used for recording image data from the IP cameras (3-1 to 3-m).
When the contents of the setting information file 19 are read into the memory 16, the contents become setting information 18. In this case, the contents of the setting information file 19 are identical to the contents of the setting information 18.
The setting information 18 includes a administrator's password 521 and per-camera information 522.
The per-camera information 522 includes a camera name 531, a camera type 532, an address (URL or IP address) 533, a camera administrator's password 534, a schedule 535, and a recording region size (byte size) 536.
FIG. 26 shows an example of process configuration of software for acquiring, storing, and distributing image data on the NDR 1 and explains operation states of the software. It should be noted that like components substantially identical to those shown in FIG. 2 relating to the present invention which will be described later are denoted by like symbols (or like symbols excluding A and B). However, this does not have an intention to limit the present invention.
A process 21 concerning image data acquisition, storage, and distribution includes a storage process 22, a setting management process 23, a reception process 24 (24-1 to 24-m), and a distribution process 25.
The storage process 22 is a process for performing read/write from/to the recording device 11 and manages which position on the recording device 11 is used as the recording region 31 (31-1 to 31-m) of a particular camera. The storage process 22 performs write of image data into the camera recording regions 31 (31-1 to 31-m) and read of image data from the camera recording regions 31 (31-1 to 31-m).
The setting management process 23 performs instructions of start, end, setting modification of processes concerning image capture, storage, and distribution and manages the processes according to the setting information 18.
The reception process 24 consists of m processes (24-1 to 24-m) for acquiring image data from the IP cameras 3 (3-1 to 3-m). According to a protocol of the IP cameras 3 (3-1 to 3-m), a request for image data is made, image data is received from the IP cameras 3 (3-1 to 3-m), and image data is transmitted to the storage process 22. In this example, one reception process 24 (24-1 to 24-m) is allocated for one IP camera (3-1 to 3-m).
The distribution process 25 is a process for distributing image data to the client PC 4 (4-1 to 4-n), i.e., receiving an image data request from the client PC 4 (4-1 to 4-n, reading out image data from the recording device 11 via the storage process 22, and transmitting the image data to the client PC (4-1 to 4-n).
According to a flow of the image data, an explanation will be given on an example of operation performed in an image storage system shown in FIG. 25.
Firstly, the operation at the image recording side will be explained.
The IP camera 3 (3-1 to 3-m) compresses captured images for each frame by using an image compression method such as the JPEG (Joint Photographic Experts Group) and transmit them in the IP packet format toward the NDR 1 in the network 2.
The image data transmitted from the IP camera 3 (3-1 to 3-m) is transmitted in the IP format through the network 2 to reach the network I/F 14.
The network I/F 14 converts the received image data in the IP format into a format to be transmitted to the control bus 13 and passes the image data to the reception process 24 (24-1 to 24-m) of the software operating on the CPU 17.
The reception process 24 (24-1 to 24-m) removes a character string for communication from the image data, adds the current time information to the image data, and transmits the image data to the storage process 22.
The storage process 22 temporarily stores the received image data in the memory 16. After accumulating 10 to 100 data pieces, the storage process 22 calculates the storage position on the recording device 11 and stores the accumulated image data via the recording device I/F in the camera recording region 31 (31-1 to 31-m) of the recording device 11.
Here, the image data from the IP camera 3-1 is stored in the camera recording region 31-1, the image data from the IP camera 3-m is stored in the camera recording region 31-m. Thus, the image data from each of the IP cameras 3 (3-1 to 3-m) is stored in the corresponding camera recording region 31 (31-1 to 31-m).
The memory 16 of the NDR 1 in recording operation contains the setting information 18 required for recording operation.
The administrator's password 521 is a password for identifying a setting modification authorized person of the NDR 1.
The per-camera information 522 has various information pieces 531 to 536 existing in the camera performing recording.
The camera name 531 is a character string assigned as a name which can be easily identified by an administrator.
The camera type 532 is a name for identifying a camera type. For example, the communication method may vary depending on the camera type. The camera type 532 is information for deciding the communication method used for acquiring image data.
The address 533 is information required by the NDR 1 to make a connection via the network 2 to the IP camera 3 (3-1 to 3-m). For example, the address 533 is an URL (Uniform Resource Locator) or an IP address of the IP camera 3 (3-1 to 3-m).
The camera administrator's password 534 is a password which is transmitted when modifying the setting of the IP camera 3 (3-1 to 3-m) from the NDR 1. For example, depending on the recording process, the setting of the IP camera 3 (3-1 to 3-m) should be modified. The camera administrator's password 534 is used when a password is required for authenticating the administrator when modifying the setting of the IP camera 3 (3-1 to 3-m).
The schedule 535 is table information indicating when imaging is performed with how many frames. For example, in the NDR 1, it is possible to perform processing by changing the frame rate between the day time and the night time.
The recording region size 536 is a byte size of the camera recording region 31 (31-1 to 31-m) allocated for the corresponding IP camera 3 (3-1 to 3-m) on the recording device 11.
Next, explanation will be given on the operation at the image distribution side.
A user who wants to view an image recorded in the NDR 1 operates the NDR reproduction software on the client PC 4 (4-1 to 4-n). Then, in the client PC 4 (4-1 to 4-n), the NDR reproduction software acquires image data from the NDR 1 and performs image display and reproduction on the screen of the client PC 4 (4-1 to 4-n).
More specifically, the NDR reproduction software on the client PC 4 (4-1 to 4-n) transmits an image distribution request in the IP format to the NDR 1 via the network 2. The image distribution request transmitted from the client PC 4 (4-1 to 4-n) is transmitted in the IP format through the network 2 to reach the network I/F 14 of the NDR 1.
The network I/F 14 converts the received image distribution request in the IP format into a format to be transmitted to the control bus 13 and transmits it to the distribution process 25 of the software operating on the CPU 17. According to the image distribution request, the distribution process 25 requests the storage process 22 to read out image data. According to the image distribution request, the storage process 22 reads out image data from the camera recording region 31 (31-1 to 31-m) via the recording device 11 and transmits it to the distribution process 25. The distribution process 25 transmits image data in the IP format from the network I/F 14 via the network 2 to the client PC 4 (4-1 to 4-n).
The NDR reproduction software on the client PC 4 (4-1 to 4-n) decodes the received image data and displays it on the screen.
Here, the camera recording region 31 (31-1 to 31-m) is created by the administrator of the NDR 1 by using the setting screen for region allocation from the client PC 4 (4-1 to 4-n).
Moreover, the administrator of the NDR 1 decides the byte size of the camera recording region 31 (31-1 to 31-m) considering the frame rate upon recording and the recording time for the IP camera 3 (3-1 to 3-m) to be connected.
FIG. 27 shows an example of recording state in the camera recording region 31-1 in the NDR 1. It should be noted that like components substantially identical to those shown in FIG. 2 relating to the present invention which will be detailed later are denoted by like symbols (or like symbols excluding A and B). However, this does not have an intention to limit the present invention.
As shown in FIG. 27, when recording image data into the camera recording region 31-1, recording is started at the head of the region and when recording reaches the end of the region, overwrite is started at the head of the region. Thus, cyclic recording is performed in an allocated region in advance without automatically extending the capacity.
Moreover, a management number (a serial number starting from 1 independent for each camera) is attached to the acquired image data of each frame. In this example, this will be called “a frame number”. When recording image data in the recording device 11, an image acquisition time and a frame number are also recorded.
When acquiring one frame of image data from the client PC 4 (4-1 to 4-n), target image data can be acquired by specifying a time or a frame number.
Moreover, the NDR 1 has a variety of setting items.
For example, there are settings of an address (an IP address or a domain name) of the NDR 1, address of the respective cameras 3 (3-1 to 3-m) for capturing an image, a schedule of a frame rate in the image capturing by each of the cameras 3 (3-1 to 3-m), a region size of the camera recording region 31 (31-1 to 31-m), and the like.
These settings are performed via the setting screen displayed on the Web browser of the client PC 4 (4-1 to 4-n) via the network 2.
It should be noted that it is possible to configure the system in such a way that any one can modify the settings or in such a way that only a administrator can modify the settings by using the password 521 set for the administrator.
Similarly, it is possible to set a password for modify setting of the camera 3 (3-1 to 3-m).
These techniques are detailed, for example, in JP-A-2005-92679 (US 2005/076176) and JP-A-2004-355724 (US 2004/244055).